Field of the Invention
The invention relates to a climate control system with blowers, in particular in agricultural or construction machinery.
Description of the Background Art
To regulate a temperature of air in a vehicle, a climate control system is usually provided, which includes a blower for fresh and circulating air intake, an evaporator and a heater.
In many climate control systems, in particular in the cabs of agricultural or construction machinery, a main blower is provided along with an additional blower that delivers fresh air to the main blower for the purpose of equalizing the high drop in pressure that is frequently present in the intake tract of the cab. A climate control system of this type is described, for example, in U.S. Pat. No. 4,531,453. In this case, a fresh air blower draws in the fresh air from the upper rear area on one side of the vehicle via a fresh air opening. The blower is situated in the rear area of the vehicle, below the driver's seat, and delivers the fresh air to a precleaner and subsequently to a filter. In a mixing chamber, the fresh air is mixed with circulating air that is drawn in via a circulating air opening situated in the rear area of the cab and via a further filter. The mixed air is subsequently conducted through an evaporator and, if necessary, through a heater before the mixed air reaches the main blower and enters the cab through discharge openings situated on the side of the cab opposite the fresh air opening, i.e. the main blower delivers this mixed air to the cab through heat exchangers situated on the intake side. The rotary axes of the blowers are situated such that they are offset and parallel to each other, the main blower being situated slightly below and upstream from the fresh air blower on the side of the discharge openings. The evaporator is oriented in the direction of the vehicle's central longitudinal axis, and the heater is situated diagonally thereto.
U.S. Pat. No. 4,467,706 discloses a construction machine having an outside air blower that is used, in particular, to maintain the air pressure within the cab above atmospheric pressure. The outside air is drawn in via filters and passed downstream. A circulating air blower is also provided—independently of the outside air blower—which draws in circulating air from the cab via filters. Downstream from the blower, the circulating air is added to the outside air stream and, together with this outside air stream, directly reaches an evaporator and heater before the temperature-regulated mixed air is supplied to the cab. The two blowers are situated in a lower region of the construction machine, in front of the cab, the rotary axes of the blowers running parallel to each other and perpendicular to the central longitudinal plane of the vehicle. The circulating air blower is a blower that has two impellers, and the intake conduit is supplied to the blower from below. The fresh air blower is situated slightly higher and upstream from the circulating blower, so that the fresh air conduit is situated such that it runs above the circulating blower, starting from the fresh air blower.
However, this known climate control system is prone to malfunction and fails to operate within desired parameters.